Drilling head



June 29 1926. 1,590,681

M. HA NFF DRILLING HEAD F iled Oct. 27, 1921 UNITED STATES PATENT OFFICE.

MAX HANFF, 0F IBEBLIN, GERMANY, ASSIGNOR TO THE FIRM ALWIN' BERGER, 0F BERLIN, GERMANY.

DRILLING HEAD.

Application filed. October 27, 1921, Serial No. 510,964, and in Germany February 5, 1821.

This invention relates to drilling heads of the type wherein an angled gear for transmitting the rotary motion, must be provided at a short distance from the tool and consequently drillings, etc, from the work iece being drilled, are liable to get into the inter-engaging parts of the elements of the gear and interfere with the rotational motion.

This is particularly the case with dentists drills comprising an angle head. llotwithstanding the well-inade and. apparently tight mounting of the drill, inillings or drillings from the teeth as well saliva and the like are very liable to find their way into the closed interior of the casing containing the angled gear.

This drawback is greatly intensified by the presence of the lubricating hole which is necessarily provided at the meshing point of the gear and is always open. The fine teeth of the bevel wheels take up the dirt which coagulates during the intervals of rest. The starting again or the drill by the dentist, which experience shows always takes place abruptly, frequently leads to a fracture of the bevel toothed wheels or at least reduces their life and eiiiciency. It is not -feasible for the drill to be repeatedly taken apart by the dentist because the latter has probably not the necessary expert knowledge or time.

A cording to this invention the casings of drill heads are provided with devices such as will allow the dentist, without loss or" time, to keep the bevel wheels and their meshing constantly under observation, and also enable the internal parts of the gear to be cleaned and kept tree from dirt by means 01 a convenient and copious supply of benzinc or other cleaning liquids as well as by mechanical treatment. The open lubricat inp; hole is dispensed with.

Some constructional forms of this invention are illustrated by way of example in the accompanying drawings, in which:

Figs. 1 and 2 show an improved head fitted with a flap lid respectively in the closed and open state.

Figs. 3 and 4 show the same head with a sliding lid. and

Fig. 5 shows the head taken apart.

Referring to Figs. 1 and 2, a is the head with a hinged flap lid. When closed the outline of the flap is scarcely visible and does not disturb the dentist in any way. A tight closure is effected in the usual manner by snapping together two tiled places, one behind the. other. The flap is opened by lifting up with the finger nail at the place 0 prepared for this purpose.

In Figs. 3 and l, the flap is replaced by sliding lid (5. In this construction it is suiticicnt for opening the lid to provide a Hat knob In Fig. 5 the asing or head consists of the two parts a and 7 which can be connected together for instance by means of small screws 5/. Of course, if desired, all the bearing surfaces may be made tight, preterably and most simply by grinding together to term as wide and smooth surfaces as possible. Instead of being applied to the angled gear as shown, the devices of this invention may, of course, be applied to other heads or casings containing driving wheels or similar parts for transmitting rotary motion through an angled drive.

ll hat I claim as my invention and desire to secure by United States Letters Patent is:

In a dental drill, a drilling head including in combination, a dust proof casing formed of a single piece of rigid material and having the form 01"" an elbow, shafts journalled through the ends of the casing and having the adjacent end portions arrano'ed at right angles and positioned at he oend of the casing, int-ernieshing gears on the adjacent ends of the shafts and within the casing, the casing being provided with an aperture in one side adjacent the bend thereof and adjacent the point of engagement of the of the gears, the aperturesbeing relatively small so that cleansing and control of the drive is possible while it is impossible to take the drive apart or alter the relative po sition of the intermeshing teeth of the gears and a removable cover the edges of which are arranged in overlapped engagement with the edges of the aperture for closing the aperture and maintaining the casing dust proof.

In testimony whereof I have afiixed my signature.

MAX ."EIANFF.

gears to permit of oiling" 

